You're right about books. lol. MAD magazine too. But the numbed brain phenomenon is the difference in television. The input goes straight to memory when you're mesmerized by TV. With books, you have your full brain active, filtering out good/bad, truth/lie. With TV, you just get an image of a decapitation fed into your memory banks and then it's on to the next image. No time to make a balanced judgement with today's fast-cut techniques. There's no telling what's being implanted in memory. Remember the hundreds of kids who had seizures in Japan while watching TV?:

http://www.cnn.com/WORLD/9712/17/video.seizures.update/

Many feel that was just some kind of programming beta test. TV is bad, bad stuff.